Two years ago this week, the world came together in Paris to sign a landmark agreement aimed at stopping the Earth's temperature from rising dangerously high.
But according to a new report from Climate Tracker, an independent research group, we're way off track to hit the target laid out in the Paris climate agreement.
The Paris Agreement pushed member nations to curb their greenhouse gas emissions, like carbon dioxide and methane, in order to keep global temperatures from increasing more than 2 degrees Celsius above pre-industrial levels. Each country submitted its own plan for reducing emissions that cause our atmosphere to trap more heat.
But if all of the signatories fulfill their pledges — and that's a big if — global temperatures will still increase by 3.2 degrees Celsius above pre-industrial levels by the end of the century, according to Climate Tracker's latest report.
President Donald Trump has pledged to pull the US out of the agreement, claiming it hurts US manufacturing — but that process that will take several years. If the US does leave, it will be the only country in the world not signed on.
What could happen if the planet exceeds the 2-degree limit
According to the Intergovernmental Panel on Climate Change (IPCC), if global temperature rise exceeds 2 degrees Celsius, climate-related risks like wildfires, sea level rise, and crop failure will be magnified.
The 2-degree limit was first established in a working paper by an economist — not a climate scientist — in the 1970s, but it has proved to be a useful rallying point for the international community.
Scientists have outlined how continued emissions could lead to the complete loss of ice sheets in Greenland over the next few centuries, which could cause sea levels to rise by 7 meters, or over 21 feet, submerging populated coastal cities like New York and Miami. In certain regions, moving past the 2-degree limit could cause average crop yields to be 25% lower — and those effects only increase the warmer it gets.
It's important to note, however, that modeling climate change is a highly complex process with many variables, so these effects are a matter of probabilities, not an absolute certainty.
The US' potential withdrawal would add 0.3 degrees Celsius of warming by 2100
Climate Tracker's report calculates that the US's withdrawal from the Paris agreement would add approximately 0.3 degrees Celsius of warming to its projections for the year 2100.
And while the report notes that carbon dioxide emissions have flattened over recent years, it's too soon to say that global emissions have peaked. Climate Tracker predicts that greenhouse gas emissions will grow between 9% and 13% from 2020-2030 based on current trends.
In order to hit the targets laid out by the Paris agreement, global greenhouse gas emissions need to peak around 2020 then rapidly fall.
But there are some positive signs. Climate Tracker estimates that policies implemented in 2017 reduced their global temperature predictions by 0.2 degrees Celsius over 2016 projections. And India and China — two of the fastest-growing economies in the world — have made significant headway in reducing the growth rate of their greenhouse gas emissions.
Nonetheless, Climate Tracker predicts emissions in India will grow approximately 7% between 2020-2030, and China's will rise 51% in the same period.
The report notes, however, that climate modeling is a tricky business with a lot of room for error.
A study published by Nature earlier this month estimates that the world will be 15% hotter in 2100 than the Intergovernmental Panel on Climate Change (IPCC) — whose work formed the basis of the Paris agreement goals — projected, based on a new set of calculations.
This new research suggests humans will probably have to reduce emissions even more steeply to avoid crossing the thresholds agreed to in Paris.